Susceptibility to neonatal streptozotocin-induced diabetes in spontaneously hypertensive rats

We studied the difference in the susceptibility to neonatal streptozotocin (STZ) diabetes between spontaneously hypertensive rats (SHR) and Wistar Kyoto rats (WKY). Two-day-old female SHR and WKY were injected intraperitoneally with 75.0 mg/kg of STZ or vehicle for control. Hyperglycemia developed in both strains at 4 days of age, but SHR were more hyperglycemic. Overt hyperglycemia developed in SHR with aging after a partial recovery from initial hyperglycemia at 10 days of age, whereas WKY did not develop significant hyperglycemia except shortly after STZ treatment. Percentage of insulin-positive B cells in total islet cells and pancreatic immunoreactive insulin (IRI) content were measured at 4 days, 10 days, 4 weeks, and 12 weeks of age. B cells per islet and pancreatic IRI content were significantly reduced in STZ-treated groups as compared with control in both SHR and WKY at 4 days of age, but later they increased significantly with aging in both strains. However, the reduction in pancreatic IRI content relative to control was significantly greater in SHR than in WKY from 4 days (-94.5 +/- 3.5%, -84.1 +/- 4.8%; p < 0.01) to 12 weeks (-97.1 +/- 2.1%, -28.0 +/- 2.5%; p < 0.05), and the reduction in B cells per islet was also greater in SHR at 4 weeks of age. These results indicated that the initial destruction of pancreatic B cells induced by STZ was greater, and the following regeneration was less in SHR than in WKY. The association of the susceptibility to neonatal STZ diabetes with the development of genetic hypertension in SHR remained to be elucidated.

Prevalence of root caries in a Japanese adult population aged 20-59 years

The purpose of the present study was to investigate the prevalence of root caries in an adult population in Japan. A total of 770 company employees aged 20-59 were examined in 1990. The subjects were all dentate and had 27.2 present teeth on the average. The proportion of gingival recession in this population ranged from 20.1% for the 20-29 year old group to 75.2% for the 50-59 year old group, with an average of 44.0%. In the present study, 3.2% of the subjects showed one or more active root caries. The prevalence of active root caries ranged from 0.4% at age 20-29 to 7.1% at age 50-59. The proportion of persons with active root caries and/or root fillings ranged from 1.3% at age 20-29 to 36.3% at age 50-59. The percentage of subjects with active and/or inactive caries and/or root fillings varied from 3.1% at age 20-29 to 43.4% at age 50-59. The prevalence of active root caries in the subjects at risk (with gingival recession) was 7.4% on the average and ranged from 2.2% at age 20-29 to 9.4% at age 50-59. The percentage of persons with active root caries and/or root fillings in the subjects at risk ranged from 6.7% at age 20-29 to 48.2% at age 50-59. The mean number of teeth with active root lesions was 0.09 per person, and the mean number of teeth with root fillings was 1.25 at age 50-59.(ABSTRACT TRUNCATED AT 250 WORDS)

[Autologous blood transfusion in transurethral resection of the prostate]

With the purpose to avoid the risk of transfusion mediated infection and complication, predeposited autologous blood transfusion was performed. From April 1990 to March 1991, transurethral resection of the prostate (TUR-P) were performed in 27 patients (mean age: 72.5 years) with benign prostatic hypertrophy (BPH). Autologous blood (200-400 ml, mean 244 ml) was predeposited 3 weeks prior to TUR-P in 18 patients (mean age: 73.9 years) and transfused during or just after the operation in 16 (five patients required some homologous blood in addition to their own banked blood). Another three patients were transfused with homologous blood only. The mean values for hemoglobin concentration were 13.7 +/- 0.4 g/dl before blood deposition and 12.8 +/- 0.5 g/dl on the day of operation (recovery rate: 92.5 +/- 2.7%). Although no complication was found in autologous blood transfusion group (11 patients), one case of systemic exanthema and one case of type C hepatitis were observed in homologous blood transfusion group (8 patients). In TUR-P, positive correlations were observed among resected prostate weight (Pro-wt), blood loss (B.) and operation time (Op-T.). Correlation efficient between Pro-wt. and B. was 0.80, that of B. and Op-T. was 0.77 and that of Pro-wt. and Op-T. was 0.85. From these results and ultransomographic measurement of the prostate weight, the amount of blood loss can be calculated preoperatively, there by the amount of blood needed for transfusion will be estimated.(ABSTRACT TRUNCATED AT 250 WORDS)

A new diabetes model induced by neonatal alloxan treatment in rats

Rats treated with streptozotocin (STZ) during the neonatal period have been used as a model of non-insulin-dependent diabetes mellitus. The present study was designed to produce another diabetes model by substituting alloxan for STZ. Male Sprague-Dawley rats of 2, 4 or 6 days of age were injected intraperitoneally with 200 mg/kg of alloxan monohydrate after 16 h fast. Control rats received vehicle alone at 6 days of age. Non-fasting plasma glucose levels in alloxan-treated rats significantly increased after 8 weeks as compared with control, as the age of alloxan treatment advanced (6.6 +/- 0.2 (S.E.M.) mM in control, 8.3 +/- 0.3 mM in 2 days, P < 0.05, 9.8 +/- 0.9 mM in 4 days, P < 0.05, 17.1 +/- 3.5 mM in 6 days, P < 0.05). For the long-term observation, alloxan-treated rats were divided into mild and severe diabetes groups. Hyperglycemia persisted in both groups until 52 weeks (6.5 +/- 0.1 mM in control, 10.3 +/- 0.7 mM in mild diabetes group, 25.3 +/- 3.6 mM in severe group), but significant albuminuria developed only in severe diabetes group. The diabetogenicity of alloxan rapidly increased during the neonatal period, and the neonatal alloxan diabetes model may be useful for studying chronic diabetic complications.

A comparison of daily fluoride intakes from food samples in Japan and Brazil

The purpose of this study was to analyse the fluoride content of Japanese infant foods and foods in Brazil and to estimate daily fluoride intake calculated for a 6-month-old infant which reflects supplemental fluoride increased from infant foods and decreasing breast-feeding and commercial milk-feeding. Fluoride concentrations of 26 samples were assessed by a modified microdiffusion method and fluoride ion selective electrode. The fluoride content varied from 0.53 to 1.33 microgram/g for milk-base formulas, from 0.46 to 2.94 micrograms/g for infant foods in Japan, and from 0.06 to 0.25 microgram/g for foods in Brazil. The daily fluoride intake was calculated according to feeding pattern. The minimum and maximum fluoride values were 0.080 mg/day and 0.248 mg/day, respectively. These fluoride intakes, expressed in milligrams per kg of fluoride intake, ranged from 0.010 to 0.033 mg F/kg body weight. No significant differences in fluoride intake values were found between Japanese infant foods and foods in Brazil. The results of this study indicate that daily fluoride intakes of Japanese infant foods and foods in Brazil could be considered within the optimal recommended level.

Separation and characterization of the C-terminal half molecule of bovine lactoferrin

The C-terminal half molecule (C lobe) of bovine lactoferrin was isolated by mild tryptic hydrolysis of lactoferrin followed by gel filtration and ion-exchange chromatography. The identity of the fragment was established by determining its N-terminal and C-terminal amino acid sequences and comparing them with the amino acid sequence of intact lactoferrin. The isoelectric point of the C lobe ranged between pH 6.2 and 6.5 as measured by isoelectric focusing on polyacrylamide gels. The circular dichroic spectrum in the range of 250 to 350 nm of the C lobe differed slightly from that of intact lactoferrin. The pattern of lectin reactivity was similar for both the C lobe and intact lactoferrin. The C lobe showed partial antigenic identity with intact lactoferrin as demonstrated by the double immunodiffusion method, and pH dependence of iron binding of C lobe is the same as that of intact lactoferrin molecule.

A 5 kDa protein (SCS23) from the 30 S subunit of the spinach chloroplast ribosome

The proteins of the 30 S ribosomal subunits from spinach chloroplasts were investigated using a radical-free and highly reducing (RFHR) method of two-dimensional polyacrylamide gel electrophoresis (PAGE). Twenty-three proteins were resolved on the gel down to the smallest protein of 5 kDa. The N-terminal amino acid sequence of the 5 kDa protein showed no homology with that of any other protein stored in databases, and the copy numbers were estimated to be 0.88 +/- 0.16 and 0.72 +/- 0.04 in the 30 S subunits and the 70 S ribosomes, respectively. The results suggest that the 5 kDa protein, which we have called SCS23, may be an essential ribosomal protein specific to spinach chloroplasts.

Evaluation of a local microsphere injection method for measurement of blood flow in the rabbit lower extremity

The precision of a modified microsphere technique to measure blood flow in the hind limb of the rabbit was determined. Regional (local) injections made via a catheter in the aorta and blood withdrawn through a catheter in the hind limb enabled deposition of a high concentration of microspheres in the tissues while minimizing the number of microspheres needed for accurate measurement. 95Niobium and 141cerium-labeled 16 microns diameter microspheres were used. Blood flow was measured in 15 locations of muscle and skin for simultaneous injections into the aorta and left ventricle (group A), simultaneous injections of a mixture into the left ventricle (group B), and ventricular injections given 1 h apart (group C). No significant differences in mean blood flow measurements were found. Correlation coefficients between local and ventricular injections ranged from 0.89-0.99 and between 0.994 and 0.999 for two simultaneous ventricular injections. The variability over time was greater, with correlations between the first and second injections ranging from 0.13-0.939. Precision of the local technique compared with the ventricular technique can be kept within 30% with five or six animals. The advantage of this technique over ventricular injections is in the measurement of blood flow in small tissue samples when the number of microspheres deposited from ventricular injections is insufficient.

[A case of asymptomatic Dandy-Walker syndrome with cerebellar hemorrhage]

A case of asymptomatic Dandy-Walker syndrome (DWS) complicated by cerebellar hemorrhage is reported. A 65 year-old man was hospitalized for investigation and treatment of disturbance of consciousness. CT scan and MRI showed a large hematoma in the posterior fossa cyst. Postoperative CT scan and MRI revealed the DWS and cerebellar hemorrhage on the left side. This patient had no symptom until 65 years of age, in spite of having DWS. There has been no such case reported in the literature to our knowledge. Derangement of secretion and absorption of cerebrospinal fluid seem to have been the cause of late-onset symptoms after a long well balanced symptom-free period.

Effects of salt loading on glucose tolerance, blood pressure, and albuminuria in rats with non-insulin-dependent diabetes mellitus

We studied the effects of salt loading on glucose tolerance, blood pressure, and albuminuria in rats with mild non-insulin-dependent diabetes mellitus (NIDDM). Two-day-old male Wistar Kyoto (WKY) rats were injected intraperitoneally (IP) with either 75.0 mg/kg streptozotocin (STZ) or vehicle as control. Salt loading was performed as 1% NaCl of drinking solution from 4 weeks until 12 weeks of age (estimated sodium intake: control, 3.14 +/- 0.28 mEq/d in tap-water group, 11.9 +/- 0.95 mEq/d in salt-loaded group; NIDDM, 2.93 +/- 0.16 mEq/d in tap-water group, 12.0 +/- 2.59 mEq/d in salt-loaded group). Oral glucose tolerance, glycosylated hemoglobin (GHb), and pancreatic insulin content at 12 weeks did not differ between the salt-loaded group and tap-water group in both NIDDM and control rats. Urinary sodium excretion was increased in salt-loaded groups of control and NIDDM rats, but systolic blood pressure did not differ among the groups (control, 151 +/- 6 mm Hg in tap-water group, 150 +/- 3 mm Hg in salt-loaded group; NIDDM, 152 +/- 3 mm Hg in tap-water group, 157 +/- 2 mm Hg in salt-loaded group). Urinary albumin excretion was significantly increased in salt-loaded groups (1,790 +/- 272 micrograms/d in control, 1,617 +/- 174 micrograms/d in NIDDM rats) compared with tap-water groups (691 +/- 75 micrograms/d in control, P less than .05; 616 +/- 69 micrograms/d in NIDDM rats, P less than .001), irrespective of STZ injection, but endogenous creatinine clearance was not different among the groups. Furthermore, renal growth was more greatly increased in salt-loaded groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Caries experience in subjects 18-22 years of age after 13 years' discontinued water fluoridation in Okinawa

The purpose of this study is to compare the state of teeth in young adults who had consumed fluoridated water from birth to 5-8 yr of age with the subjects who had non-fluoridated water. The sample consisted of 117 18-22-yr-old female nursing school students. The data obtained in dental examinations were sorted according to their place of residence, and then divided into groups depending on whether their place of residence had been supplied with fluoridated water or not. The fluoride concentration in the water had been 0.7-1.0 ppm in the six water supply systems which were under the control of the US military base. In the subjects who had fluoridated water, the following differences were found when compared to the control subjects: missing teeth and highly progressed caries occurred less frequently; significantly lower caries prevalence was present on free smooth and approximal surfaces; the overall DMFT differences in favor of the fluoridated subjects were small and non-significant.

Synthesis and anti-human immunodeficiency virus type 1 (HIV-1) activity of 3-substituted derivatives of 3'-azido-3'-deoxythymidine (AZT), and inhibition of HIV-1 reverse transcriptase by their 5'-triphosphates

Various 3-substituted 3'-azido-3'-deoxythymidine analogs (2a-i) were prepared by the reaction of 3'-azido-3'-deoxythymidine (1), AZT with N,N-dimethylformamide dialkylacetal or alkyl bromide in the presence of base and their activities against human-immunodeficiency virus type-1 (HIV-1) were evaluated. The corresponding 5'-triphosphate analogs (9) were also synthesized in order to examine inhibition of HIV-1 reverse transcriptase activity. Beyond expectation, some N3-derivatives of AZT were found to reserve the anti-HIV-1 activity to some extent. Among the compounds (2a-i) obtained, 3-allyl-AZT (2e) was the most active against HIV-1 replication in MT-4 cells in vitro with an EC50 value of 0.9 microM. 3-Allyl-AZT 5'-triphosphate (9e), however, exhibited no inhibition of HIV-1 reverse transcriptase activity.

Mutans streptococci in saliva and interdental spaces after topical applications of an antibacterial varnish in schoolchildren

The effect of a chlorhexidine-containing varnish on the levels of mutans streptococci in saliva and in interdental spaces was investigated in 33 15-year-old schoolchildren. Each child was treated with an active (1% chlorhexidine; 1% thymol) and a placebo varnish preparation following the split-mouth technique. The varnishes were applied twice in small amounts into upper interdental areas with a 2-d interval. Mutans streptococci in saliva and interdental plaque was sampled and enumerated during 3 months. The results showed an immediate reduction of the number of interdental mutans streptococci on both test and placebo side after the varnish applications. The levels, however, were significantly lower in the test quadrants compared with the placebo-treated sides after 8, 30 and 90 d. Thus, the findings indicate a slower recolonization in interdental spaces treated with the active preparation. The levels of mutans streptococci in saliva were significantly reduced 1 and 3 months after varnish treatment, suggesting a long-term effect of the antibacterial varnish.

In vitro and in vivo studies of the growth inhibitory effect of a newly synthesized peptide, obiopeptide-1, on mice-bearing methylcholanthrene-induced murine tumours

Novel synthetic Obiopeptide (Obi-1), Glycil-penta-Glutamate, as an immunoregulator, injected intramuscularly to methylcholanthrene (MC) induced tumour bearing mice at 30-100 micrograms per mouse weekly, significantly inhibited tumour growth, compared to that of the untreated control. Numbers of mononuclear cells (MNC) in the spleen obtained from Obi-1 treated and untreated mice were reduced to 64% and 10% of the normal levels, respectively. In histopathological findings, variations of MNC in the spleen was observed in colonies of large MNC and lymphocytes in Obi-1 treated red marrow, while untreated one showed only scattered number of small lymphocytes. A significant O2- production was noted in monolayers of normal macrophages incubated with 0.5 mg Obi-1/ml for 48 hr. Cytotoxicity of spleen MNC cultured with Obi-1 against MC-tumour, Meth A, P-815 and YAC-1 target cells showed less than 10% cytotoxic activity in almost all experiments.

8-Methyladenosine-substituted analogues of 2-5A: synthesis and their biological activities

8-Methyladenosine-substituted analogues of 2-5A, p5'A2'p5'A2'p5'(me8A), p5'A2'p5'(me8A)2'p5'(me8A), p5'(me8A)2'p5'(me8A)2'p5'(me8A), and p5'(me8A) 2'p5'A2'p5'A, were prepared via a modification of a lead ion-catalyzed ligation reaction. These 2-5A monophosphates were converted into the corresponding 5'-triphosphates. Substitution of an 8-methyladenosine residue at the third position (2'-terminus) of the oligonucleotides increased the stability to snake venom phosphodiesterase digestion. Both binding and activation of mouse liver 2-5A dependent ribonuclease (RNase L) by the various 8-methyladenosine-substituted 2-5A analogues were examined. Among the 8-methyladenosine-substituted trimer analogues, the analogues with 8-methyladenosine residing in the 2'-terminal position showed the strongest binding affinity and were several times more effective than 2-5A itself as an inhibitor of translation.

[Bilateral traumatic hemorrhage in the basal ganglia: report of two cases]

Hematomas of the basal ganglia in head injury have long been recognized by pathologists with an interest in head injury but their mechanism has not been revealed clearly. We report two cases of bilateral traumatic hemorrhage in the basal ganglia. Case #1, a 17-year-old male was admitted to our hospital immediately after a traffic accident. Neurological examination revealed that the patient was comatose and had right hemiparesis. CT scan showed bilateral hemorrhage of the basal ganglia and subarachnoid hemorrhage in the perimesencephalic cistern. MRI showed high signal intensity areas in the bilateral basal ganglia, perimesencephalic cistern, cerebral white matter and corpus callosum. The patient was diagnosed as having diffuse axonal injury coinciding with bilateral hemorrhage of the basal ganglia. Stereotactic aspiration for the hematoma of the left basal ganglia was carried out. Case #2, a 75-year-old male was admitted immediately after falling from the roof of his house. Neurological examination revealed no neurological deficit except for headache and nausea. CT scan on the day of injury revealed no abnormality. But CT scan 12 hours following the injury showed bilateral hemorrhage of the basal ganglia. Blood pressure of the patient was within normal range and he was diagnosed as having traumatic bilateral intracerebral hematoma. Conservative treatment was carried out and the patient was discharged 7 days after injury with no neurological deficit. The mechanism of traumatic hemorrhage of the basal ganglia has not been clear. In case #1, diffuse axonal injury (DAI) may have played an important role in the bilateral hemorrhage. But in case #2, non-DAI factor such as vasoparalysis syndrome may have existed.(ABSTRACT TRUNCATED AT 250 WORDS)

Spontaneous recovery from non-insulin-dependent diabetes mellitus induced by neonatal streptozotocin treatment in spontaneously hypertensive rats

We studied the long-term change in glycemic level in a model of non-insulin-dependent diabetes mellitus (NIDDM) induced by neonatal streptozotocin (STZ) treatment in spontaneously hypertensive rats (SHR). Two-day-old male SHR were intraperitoneally injected with 37.5 to 75.0 mg/kg of STZ or vehicle alone as control. According to nonfasting plasma glucose levels at 12 weeks of age, rats were divided into mild (less than 16.8 mmol/L) and severe (greater than or equal to 16.8 mmol/L) diabetes groups. In the mild diabetes group (n = 5), plasma glucose decreased significantly from 14.2 +/- 1.8 mmol/L (mean +/- SEM) at 20 weeks to 7.3 +/- 0.3 mmol/L at 52 weeks (P less than .05) with progressing age. At 52 weeks, overnight fasting plasma glucose levels were significantly lower and serum immunoreactive insulin (IRI) was higher than in controls, respectively (4.1 +/- 0.3 v 5.7 +/- 0.3 mmol/L, P less than 0.01; 625 +/- 50 v 409 +/- 50 pmol/L, P less than .05), and insulinoma was found in 60% of rats. Therefore, the recovery from hyperglycemia may be attributed to the development of insulinoma. In the severe diabetes group (n = 6), plasma glucose remained high until 28 weeks (27.2 +/- 1.5 mmol/L), but thereafter decreased with age, as it did in the mild diabetes group (13.7 +/- 3.5 mmol/L at 52 weeks, P less than .005). However, no insulinoma was found, and the mechanism for the recovery was unclear. The present study demonstrates that hyperglycemia spontaneously ameliorates in a neonatal STZ diabetes model of SHR, although this phenomenon may be strain-related.

[Instrumentation surgery for tumor of the spine]

Spinal instrumentation surgery has come into wide use recently, especially for tumor of the spine. It is very effective for fixing the spine for relieving the patient from pain. But the decision about the indication of instrumentation surgery for tumor of the spine must be made carefully. In cases of double malignant tumors including spinal tumor, it is hard to decide how to treat tumor of the spine. We report a case of 78-year-old male with multiple myeloma of the cervical spine and cancer of the prostate. The patient had been in good health until one year previously, when he started to complain of nuchal pain. He became bedridden with loss of voluntary control of the right upper extremity for the last two months. Then he was admitted to our hospital and radiological examination was carried out. It revealed tumor of the cervical spine and it seemed to be bone metastasis. Further examination revealed that the patient was suffering from multiple myeloma and cancer of the prostate. The tumor of the spine was diagnosed as either multiple myeloma or metastasis of cancer of the prostate. Spinal instrumentation surgery using Luque-rod was carried out as one of the comprehensive treatment plans for double malignant tumors. The instrumentation surgery was effective for fixing the spine and improving the patient's quality of life. In operative procedures, intraoperative spinal cord monitoring was carried out. Intraoperative spinal cord monitoring was indispensable for preventing spinal cord injury. The tumor of the spine was diagnosed as multiple myeloma by pathological examination.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood pressure changes associated with hyperinsulinemia or long-standing diabetes mellitus in spontaneously hypertensive rats

We studied the long-term change in blood pressures of spontaneously hypertensive rats (SHR) treated neonatally with streptozotocin (STZ). Two-day-old male SHR were injected intraperitoneally with 37.5-75.0 mg/kg STZ or with vehicle as control. STZ-treated SHR were divided into mildly or severely diabetic groups according to the nonfasting plasma glucose level at age 12 weeks (the former less than 300 mg/dl, the latter greater than or equal to 300 mg/dl). In the mildly diabetic group (MD) (n = 5), body weight increased and nonfasting plasma glucose was normalized. At 52 weeks of age, fasting plasma glucose levels were lower than controls owing to hyperinsulinemia, and insulinomas were found in 60% of rats. The systolic blood pressure (SBP) as measured by a tail-cuff method, decreased after 40 weeks, and the mean BP from 44 to 52 weeks (188 +/- 4 mmHg) was significantly lower than that in the control group (209 +/- 3 mmHg, p less than 0.01). In the severely diabetic group (SD) (n = 6), hyperglycemia persisted until 52 weeks, although its severity became less marked. BP in the SD group increased after 36 weeks, and the mean BP from 44 weeks to 52 weeks (224 +/- 5 mmHg) was significantly higher than control (p less than 0.05). The present study demonstrated that hypertension was ameliorated in SHR associated with hyperinsulinemia, and deteriorated with long-standing diabetes mellitus.

Synthesis and anti-human immunodeficiency virus (HIV-1) activity of 3'-deoxy-3'-(triazol-1-yl)thymidines and 2',3'-dideoxy-3'-(triazol-1-yl)uridines and inhibition of reverse transcriptase by their 5'-triphosphates

3'-Deoxy-3'-(1,2,3-triazol-1-yl)thymidines (5a, 6a, 8a, 11a, and 12a) and 2',3'-dideoxy-3'-(1,2,3-triazol-1-yl)uridines (5b, 6b, 8b, 11b, and 12b) were synthesized as cyclic analogues of 3'-azido-3'-deoxythymidine (AZT) and 3'-azido-2',3'-dideoxyuridine (CS-87) by the cyclization of 5'-trityl derivatives (1a, b) of AZT and CS-87 using alpha-ketophosphorus ylides and with acetylenic compounds followed by deprotection of the 5'-trityl group. It was hypothesized that the triazole nitrogen atoms could mimic and distorted azido group. However, no significant activity against human immunodeficiency virus type 1 (HIV-1) was observed with any of these compounds. 5'-Triphosphates (17a and 18a, b), prepared from 5a and 6a, b, were inactive against HIV-1 and Rauscher murine leukemia virus (RLV) reverse transcriptases.

SDS-polyacrylamide gel electrophoretic patterns of human parotid saliva treated with polyvinylpyrrolidone-iodine in vitro

In the intraoral application of polyvinylpyrrolidone-iodine (PVP-I) as an antimicrobial agent, a color fading phenomenon is observed that might be caused by the binding of iodine with saliva. We have investigated the binding of iodine with saliva as iodine binding factor (IBF). The presence and characteristics of the IBF were investigated in parotid saliva stimulated by sour lemon drops, unstimulated parotid saliva, and whole saliva. A high level of the binding ability with iodine was observed in stimulated parotid saliva with the treatment of PVP-I compared with the unstimulated, but there were no significant differences in the amounts of total proteins between the stimulated and unstimulated. Electrophoretic patterns of saliva treated with PVP-I and untreated were examined to detect the IBF. The protein band of SDS-polyacrylamide gel electrophoresis near M.W. 60,000 of stimulated parotid saliva disappeared after treatment of PVP-I. This evidence indicates that the color fading phenomenon of PVP-I is associated with a polypeptide level in saliva.